Immunosenescence revisited. Does it have any clinical significance?

Immunosenescence refers to the influence of aging on the immune system. Numerous problems are encountered in studying this topic, the main one being the influence of concomitant disease. Despite the great efforts that have been devoted to research in this field, the results of studies performed to date have not been convincing and, until now, no sound scientific evidence has emerged to show that immunosenescence is clinically significant. The only possible exceptions to this are the discovery of a selective defect in cell-mediated immunity and the reactivation of varicella zoster virus. Therefore, many more, and better designed, studies will have to be conducted before the full clinical impact of immunosenescence can be delineated.

The influence of open-heart surgery on survival of patients with co-existent surgically amenable lung cancer (stages I and II).

OBJECTIVE: The evaluation of the influence of open-heart surgery on the survival of patients with co-existent surgically amenable lung cancer stages I and II. METHODS: A retrospective, observational study was conducted in a tertiary centre for cardiothoracic surgery. From 1988 to 1995, 121 consecutive patients underwent pulmonary resection for stages I-II primary non-small cell bronchogenic carcinoma. Eighty seven of them had merely a lung carcinoma necessitating resection, 34 had in addition defined coronary-artery disease and consequently were also subjected to open-heart surgery. Results were statistically computed. RESULTS: Follow-up was complete in 117/121 patients, 96.7% (83/87, 95.4% and 34/34, 100% in respective groups). Both groups were matched with regard to preoperative features possibly influencing survival. Median long term survival time was 4.3 years overall, 5.8 years for patients merely undergoing lung resection and 4.2 years for them undergoing open-heart surgery as well; this difference was not statistically significant (log-rank test: chi2 0.92, df= 1, P = 0.34), indicating no or limited influence of open-heart surgery on survival of patients with surgically amenable co-existent lung carcinoma. No relationship was found between survival and age, tumour stage, and histopathology. However, metastatic disease as cause of death was significantly increased in patients undergoing open-heart surgery (5/8 vs. 10/33, P = 0.0898), indicating a possible promotion of metastatic spread of co-existent lung carcinoma by this procedure. Overall perioperative mortality rate was 10/121, 8.3%, for the greater part the result of a relatively high mortality rate in the group of patients undergoing heart as well as lung surgery (6/34, 17.6%), underscoring the great risks involved in these patients, the mortality rate for lung resection alone being comparably low 4/87, 4.6% (P = 0.0191). CONCLUSION: Open-heart surgery for defined coronary-artery disease in patients with surgically amenable lung carcinoma carries a substantially higher perioperative risk, but has no influence on long term results. Metastatic spread is possibly promoted by open-heart surgery. Optimal treatment, consisting of complete revascularization and appropriate lung resection, is therefore sufficiently justified by these results.

Synchroneously occurring lung cancer (stages I-II) and coronary artery disease: concomitant versus staged surgical approach.

OBJECTIVE: The assessment of the best surgical approach in patients with synchroneously occurring lung cancer (stages I and II) and coronary artery disease: concomitant or staged. METHODS: A retrospective, observational study was conducted in a tertiary centre for cardiothoracic surgery. From 1988-1995, 34 patients underwent pulmonary resection for stages I-II primary bronchogenic carcinoma and open-heart surgery (almost always coronary-artery bypass grafting), either concomitantly (n = 24) or in a staged procedure (n = 10). Mean interval between operations was 33.9 +/- 34.7 days (range: 12-120 days). Results were statistically computed. RESULTS: Preoperatively both groups were perfectly matched. Follow-up was 100%. Long term survival, median 4.2 years, was comparable in both groups (log-rank test: chi2 0.30; df = 1; P = 0.58), indicating no influence on survival from performing either a concomitant or staged procedure. No relation could be demonstrated between survival and age, histopathology or extent of tumour; nor in the concomitantly operated group between survival and timing of lung resection in relation to extra-corporeal circulation. Overall peri-operative mortality was 6/34, 17.6%, but a large difference was noted between the two groups (5/24, 20.8% vs. 1/10, 10%; P = 0.64), underscoring the greater risk involved in the concomitant procedure, although this difference was not statistically significant because of small numbers. CONCLUSIONS: No difference in survival between the two groups, one operated upon in a staged procedure, the other concomitantly, could be demonstrated. However, the greater perioperative risk makes the concomitant procedure less attractive, and the staged approach the preferred one. Interval between operations can be individualized according to the clinical status of the particular patient to a period as short as 2 weeks.

[Special attention intensive care in the Netherlands once again]. / Nogmaals het aandachtsgebied intensive care in Nederland.

The organizational structure of intensive care departments is still under debate. 'Open' (without) or 'closed format' (with intensivists), that is the question. However, various studies establish that the presence of full-time intensivists reduces mortality rates in intensive care units substantially. Currently, only a minority of Dutch hospitals have properly staffed intensive care units, despite clear guidelines. It is estimated that yearly 250 to 600 lives could be saved. While the capacity of training intensivists in the Netherlands has recently been increased enormously, only a faction of young intensivists will under the circumstances be able to find jobs. More jobs should be created, for the sake of patients and young doctors as well.

Percutaneous removal of a knotted pulmonary artery catheter using a tracheostomy dilator.

STATEMENT OF FINDINGS: This case report describes removal of a knotted, subclavian, pulmonary artery catheter using a tracheostomy dilator. With this simple method an invasive procedure might be averted.

Pharmacokinetics of cefradine, sulfamethoxazole and trimethoprim and their metabolites in a patient with peritonitis undergoing continuous ambulatory peritoneal dialysis.

Cefradine and co-trimoxazole pharmacokinetics were studied in a patient with peritonitis that complicated continuous ambulatory peritoneal dialysis (CAPD). Concentrations in the plasma reached after oral administration of 500 mg cefradine four times daily and 400/80 mg co-trimoxazole four times daily were for cefradine 100 micrograms/ml, for trimethoprim 15 micrograms/ml, and for sulfamethoxazole 100 micrograms/ml, respectively. In the dialysate concentrations were reached of 35-70 micrograms/ml cefradine, 2-5 micrograms/ml trimethoprim and 8-17 micrograms/ml sulfamethoxazole. The values for sulfamethoxazole are regarded too low to be clinically effective. Half-lives, protein binding values and CAPD clearances are presented. Low CAPD clearances were obtained during the night and high values during the day. The dosage yielded too high plasma trimethoprim concentrations, while sulfamethoxazole dialysate concentrations were too low. It seems questionable therefore whether co-trimoxazole can be used orally for the treatment of CAPD peritonitis.